JPH1152807A - Cleaning device for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device for an image forming device capable of excellently removing matter stuck on a photoreceptor, while reducing the size and cost, with a simple constitution. SOLUTION: In the cleaning device 11 for the image forming device for cleaning toner remaining on the photoreceptor 1 after a transfer, generated after a toner image is transferred to a transfer paper P, the bristle members 33 and 35 of a cleaning brush 15 rotated in contact with the photoreceptor 1 consist of at least two kinds of brushes, for carrying the toner remaining after the transfer, removed from the photoreceptor 1, to a toner recovering part side. Thus, the cleaning brush used for various kinds of image forming devices using various kinds of photoreceptors and toner can be easily constituted and the cleaning brush and device are made compact and inexpensive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device of an image forming apparatus for cleaning a transfer residual toner on a photoreceptor generated after a toner image is transferred onto transfer paper.

[0002]

2. Description of the Related Art A method of cleaning a transfer residual toner on a photoreceptor after transfer of a toner image onto a transfer sheet by pressing a blade against a photoreceptor has been disclosed in Japanese Patent Application Laid-Open No. 55-41452. A method of conveying the toner cleaned by the cleaning brush is disclosed in Japanese Patent Application Laid-Open No. 58-144875. Further, a cleaning brush for removing foreign matter on the photoconductor by uniform abrasion of the photoconductor layer of the photoconductor is disclosed in Japanese Utility Model Registration No. 2520078.

In the conventional method of cleaning the transfer residual toner on the photoconductor, cleaning by pressing a rubber-like blade against the photoconductor is widely adopted. Also, in order to transport the cleaned toner, a cleaning brush that transports the toner cleaned by the blade from the photoconductor is widely provided by providing a certain nip to the photoconductor and bringing the cleaning brush into contact with the photoconductor and rotating the photoconductor. Has been adopted.

[0004]

The brush roller of this cleaning brush is pressed against the photosensitive member in order to surely transfer the transfer residual toner cleaned from the photosensitive member, but has too much rigidity with respect to the photosensitive member. Trying to convey with a bristle brush will wear the photosensitive layer on the surface of the photoreceptor. However, if the amount of wear becomes non-uniform in the longitudinal direction of the photoreceptor, the amount of charge in the longitudinal direction of the photoreceptor becomes non-uniform, and the image formed image is disturbed.

Further, various additives are added to the toner for various purposes in addition to the resin material serving as a base. Various additives are applied to the transfer paper as well as the toner. Although the additive exerts an effective effect for each purpose, if it is released from toner or transfer paper over time, it will adhere to the photoreceptor. Then, since this additive is a fine particle, it is difficult to clean it with a cleaning blade.

For this reason, as shown in FIG. 5A, the toner 1 starts with fine particles released from toner or transfer paper.
00 is accumulated. Since the accumulated toner 100 is blocked by the additive, it is difficult to clean the toner with the cleaning blade 101. Then, a large amount of toner adheres to the photoconductor 1 due to the gradually accumulated toner 100. Therefore, for example, in an image forming apparatus in which a white portion is determined by exposure, the exposure is not transmitted to the photosensitive layer due to the presence of the toner fixing portion. There is an inconvenience that a medaka image defect 103 occurs at a certain pitch Z in the circumferential direction.

In order to provide a desired bristle brush for eliminating the above-mentioned abrasion of the photosensitive layer and the medaka-like image defect 103, the loop-like bristle of the conventional brush is made of fiber having twist,
A brush weaving method in which the twist position of the fiber is out of the range of the contact position with the photoconductor is disclosed. However, according to the above-mentioned method, even if it is good at first, unevenness occurs in the photosensitive layer.

[0008] If a bristle brush having just the right thickness is formed, the brush becomes very special and very expensive.

Further, the image forming apparatus is provided with a transfer device for transferring the toner image visualized on the photosensitive member from the photosensitive member to a transfer sheet. As the transfer device, a method of transferring a toner image onto transfer paper by applying a predetermined voltage is widely adopted.

However, the voltage value for maintaining the transfer efficiency of the toner in the transfer device varies depending on the peripheral speed of the photosensitive member, the type of transfer paper, the environment, and the like. Therefore, depending on the above-mentioned change factor, a considerably high transfer voltage value is applied.
In the transfer step, in particular, in a portion not passing through the paper (outside the paper area), the potential on the photoconductor after the transfer becomes extremely high. Then, the electrostatic attraction between the photoconductor and the toner increases, and it becomes extremely difficult to clean the toner with the cleaning device.

Therefore, in order to remove the potential on the photosensitive member after the transfer before the cleaning, the PCC (Pr) is conventionally used.
e Cleaning Charge) is also employed. However, this leads to an increase in the size and cost of the device. Therefore, a method has been adopted in which the cleaning brush is made of a medium conductive material so that the photosensitive member is neutralized before the cleaning blade is cleaned.

In order to form the cleaning brush with a medium conductive material, a method of mixing a conductive material such as a carbon-based material into the bristle brush material has been widely adopted. In addition, as described above, in order to remove the deposits on the photoreceptor with the cleaning brush, the bristle brush needs to have rigidity. Therefore, a bristle brush made of a medium conductive material having a predetermined resistance while maintaining a predetermined rigidity is required. However, it is very difficult in terms of a manufacturing method to achieve both of the necessary items with one type of bristle brush.

The present invention has been made in view of the above circumstances, and provides a cleaning apparatus for an image forming apparatus which has a simple structure and which can effectively remove deposits on a photoreceptor while reducing the size and cost. It is intended to be.

[0014]

According to a first aspect of the present invention, in a cleaning device of an image forming apparatus for cleaning a transfer residual toner on a photosensitive member, the transfer residual toner removed from the photosensitive member is transferred to a toner collecting section. The bristle member of the cleaning brush that rotates in contact with the photoreceptor so as to be conveyed is composed of at least two types of brushes.

According to the first aspect of the present invention, in order to transport the toner removed from the photoreceptor to the collection side, the cleaning brush rotating in contact with the photoreceptor comprises at least two types of bristle brushes. Therefore, a cleaning brush used for various image forming apparatuses using various photoconductors and toners can be easily configured, and the cleaning brush and the cleaning device can be reduced in size and cost.

According to a second aspect of the present invention, in the first aspect, the bristle members of the cleaning brush have different rigidities.

According to the second aspect of the present invention, the cleaning brush is composed of bristle brushes having different stiffness, so that the deposits on the photoreceptor are removed with time without unevenly abrading the photosensitive layer. Can be easily done.

According to a third aspect of the present invention, in the first aspect, the bristle member of the cleaning brush is made of a different material.

According to the third aspect of the present invention, since the cleaning brush having bristle brushes of different materials is used, the potential of the photosensitive member can be controlled by the cleaning brush after the transfer, and the photosensitive layer is worn unevenly. The deposits on the photoreceptor can be removed without the need.

According to a fourth aspect of the present invention, in the first aspect of the invention, each bristle member is formed in a spiral shape so as to have a plurality of strips with respect to the cored bar. And

According to the fourth aspect of the present invention, the plurality of bristle brushes are spirally formed so that the core bar has a plurality of strips, so that the helical pitch (pile width) of each bristle brush is formed. ), The arrangement ratio of the plurality of bristle brushes can be easily controlled, so that various photoconductors, toners, and transfer devices can be flexibly used.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the relative linear velocity at the contact portion between the photosensitive member and the cleaning brush is different at least for a certain time.

According to the fifth aspect of the present invention, the plurality of bristle brushes are each exposed by setting the relative linear velocity at the contact portion between the photosensitive member and the cleaning brush to a different speed, not a constant speed, for at least a certain time. It can contact the body without unevenness. For this reason, bristle brushes that are flexibly used in various photoconductors, toners, and transfer devices can reliably exert their effects.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an image forming apparatus according to the present invention, and a photoconductor 1 rotates in an R direction. This photoconductor 1
A charging device 3, an exposure device 5, a developing device 7, a transfer device 9, and a cleaning device 11 are provided in the vicinity of the periphery of the device.

The drum surface 1a of the photoconductor 1 is charged by the charging device 3.
Are uniformly charged to a predetermined voltage. The exposure device 5 irradiates light on the contents of the document placed on the contact glass and exposes the light with the reflected light, whereby a latent image is formed on the photoconductor 1. The developer of the developing device 7 is sent to the developing roller 7a, and the latent image on the drum surface 1a of the photoconductor 1 is developed.

The toner image on the photoreceptor 1 is transferred to the photoreceptor 1 by the action of the transfer device 9 on the charge applied to the back surface of the transfer paper P.
Is transferred to the transfer paper P by the electrostatic charge. The transfer residual toner remaining after the transfer is scraped off the drum surface 1 a of the photoconductor 1 by the cleaning blade 13 of the cleaning device 11.

FIG. 2 shows the cleaning device 11 shown in FIG.
The cleaning device 11 includes a cleaning blade 13, a cleaning brush 15, a flicker bar 17, a collecting coil 19, and a cleaning case 2.
1. It has a cleaning inlet seal 23 and the like.

The cleaning case 21 has a cleaning inlet seal 23 in a gap between the drum surface 1a of the photoreceptor 1 and a cleaning blade 13 and a cleaning brush 15 fixed on the upper part thereof in a substantially parallel manner (vertical direction in FIG. 2). I have. The cleaning brush 15 is arranged close to the drum surface 1a of the photoreceptor 1 and rotates in the B direction. The collection coil 19 is arranged behind the cleaning brush 15 and rotates in the B direction.

The photosensitive member 1 rotates at a peripheral speed S1 (mm / sec) along the direction A (clockwise), while the cleaning brush 15 rotates at a peripheral speed S2 (clockwise) along the direction B (counterclockwise). mm / sec). By setting the peripheral speed S1 of the photoconductor 1 and the peripheral speed S2 of the cleaning brush 15 in FIG. 1 to be different from each other, various hairs of the cleaning brush 15 do not damage the photoconductor 1 excessively. The cleaning brush 15 can remove the deposits on the photoreceptor 1 and reliably remove the potential of the photoreceptor 1.

The cleaning blade 13 is connected to the transfer device 9
The transfer residual toner that has not been completely transferred is dammed so as not to leak downstream of the cleaning blade 13 in the direction A. Then, the clogged residual toner is conveyed from the photoconductor 1 by the cleaning brush 15 rotating on the drum surface 1a of the photoconductor 1 at the peripheral speed S2.

The transfer residual toner conveyed by the cleaning brush 15 is peeled off by the flicker bar 17 and transferred to the collection coil 19. Thereafter, the transfer residual toner is transported from the recovery coil 19 to a recovery tank member (not shown).

FIG. 3 shows an example of the structure of the cleaning brush 15.
It has one and two types of different bristle brushes 33, 35. The core metal 31 is cylindrical or cylindrical. The bristle brushes 33 and 35 are made of different materials and / or have different rigidities, and the bristle brushes 33 and 35 are composed of a large number of bristles woven into a base cloth. Have been. The bristle brushes 33 and 35 are
Is spirally adhered around the periphery of the wire.

FIG. 4 shows another example of the structure of the cleaning brush 15. The cleaning brush 15 includes a core 131, three different types of bristle brushes 133, 135, and 13.
Seven. The core metal 131 has a columnar or cylindrical shape, and is made of a different material and / or a different rigidity. These bristle brushes 133, 135, and 137 are
Is spirally adhered in a three-line shape. Bristle brush 13
3, 135, 137 are composed of a large number of bristles woven into a base cloth, and the pile width (spiral pitch) of each brush is indicated by d (mm), e (mm), and f (mm). .

The bristle brush 133 has a hair thickness a (denier /
The filaments (d / f)) are made of an insulation-resistant material, and the bristle brush 135 is made of a b (d / f) thick insulation-resistant material. The bristle brush 137 has a hair thickness c (d
/ F), the photosensitive member 1 is made of a medium conductive material in order to enable static elimination. Therefore, the hair thickness a of the bristle brush 133
Is very thick and very rigid, and the bristles b of the bristle brush 135 are flexible and thin.

By changing the pile width in accordance with various photosensitive members 1 and toners in this manner, the cleaning brush 15 capable of removing extraneous matter on the photosensitive member 1 without excessively damaging the photosensitive member 1. Can be easily formed, and the cleaning brush 15 can surely remove the potential of the photoconductor 1 after the transfer.

Incidentally, the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the claims. For example, the image forming apparatus is not limited to a copying machine but includes a facsimile, a printer, and the like using a photoconductor. The number of the bristle brushes of the cleaning brush is not limited to 2 or 3, and may be set to 4 or more.

[0037]

According to the first aspect of the present invention, since the bristle brush of the cleaning brush is composed of at least two types, it is used in various image forming apparatuses using various photoconductors and toners. The cleaning brush can be configured easily, and the size and cost of the cleaning brush and the cleaning device can be reduced.

According to the second aspect of the present invention, since the cleaning brush is constituted by the bristle brushes having different stiffness, the deposits on the photoreceptor can be removed over time without unevenly abrading the photosensitive layer. Can be easily removed.

According to the third aspect of the present invention, since the cleaning brush having a bristle brush of a different material is used, the potential of the photosensitive member can be controlled by the cleaning brush after the transfer, and the photosensitive layer is worn unevenly. Without having to do this, it is possible to remove deposits on the photoreceptor.

According to the fourth aspect of the present invention, each of the plurality of bristle brushes is formed in a helical shape so that the core bar has a plurality of strips. ), The arrangement ratio of the plurality of bristle brushes can be easily controlled, so that various photoconductors, toners, and transfer devices can be flexibly used.

According to the fifth aspect of the present invention, the relative linear velocities at the contact portion between the photosensitive member and the cleaning brush are different from each other at least for a certain period of time, not at a constant speed. The photosensitive member can be contacted without unevenness. For this reason, bristle brushes that are flexibly used in various photoconductors, toners, and transfer devices can reliably exert their effects.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an image forming apparatus including a cleaning device of the present invention.

FIG. 2 is a diagram showing the cleaning device shown in FIG. 1 in detail.

FIG. 3 is a perspective view showing an embodiment of a cleaning brush of the cleaning device.

FIG. 4 is a diagram showing an embodiment of another cleaning brush of the cleaning device.

FIG. 5 is a diagram illustrating a cleaning device in a conventional image forming apparatus.

[Explanation of symbols]

 P Transfer paper 1 Photoconductor 11 Cleaning device 15 Cleaning brush 31 Core bar 33, 35 Bristle brush

Claims (5)

[Claims] In a cleaning device of an image forming apparatus for cleaning a transfer residual toner on a photosensitive member, the transfer device rotates in contact with the photosensitive member in order to convey the transfer residual toner removed from the photosensitive member to a toner collecting unit side. A cleaning device for an image forming apparatus, wherein a bristle member of the cleaning brush comprises at least two types of brushes. 2. The cleaning device for an image forming apparatus according to claim 1, wherein the bristle members of the cleaning brush have different rigidities. 3. The cleaning device according to claim 1, wherein the bristle members of the cleaning brush are made of different materials. 4. The cleaning device of an image forming apparatus according to claim 1, wherein each bristle member is formed in a spiral shape so as to have a plurality of strips with respect to a cored bar. 5. The cleaning device for an image forming apparatus according to claim 4, wherein a relative linear velocity at a contact portion between the photoconductor and the cleaning brush differs at least for a certain time.